"He is mar" not he is ma, or he is man. He is mar most likely means he is Maro. So you ask who the hell in the show is named Maro? Nobody, but one man was, Virgil Maro who led Dante through the hell. Patrick was originally named Daniel, name resembles to Dante, and William Blake was the one responsible for the artwork named Virgil and Dante at the gates of hell, he also wrote The Tyger which we all know. Creators like to play with clues, and they wont give away anything merely important cause it would be spoiled and probbably boring. But if you do some research and tap into the mind of creator, it makes sense.